Abstracted part of local providers data directory management.

Core/ProviderBase.cs

@@ -0,0 +1,46 @@
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using ScrewTurn.Wiki.PluginFramework;
+
+namespace ScrewTurn.Wiki {
+
+	/// <summary>
+	/// Implements a base class for local file-based data providers.
+	/// </summary>
+	public abstract class ProviderBase {
+
+		private object _syncLock = new object();
+
+		private bool _dataDirectoryAlreadyRead = false;
+		private string _dataDirectory = null;
+
+		/// <summary>
+		/// Sets the data directory.
+		/// </summary>
+		/// <param name="dataDirectory">The data directory.</param>
+		protected void SetDataDirectory(string dataDirectory) {
+			lock(_syncLock) {
+				if(_dataDirectoryAlreadyRead) throw new InvalidOperationException("Cannot set data directory when it's already been read");
+				_dataDirectory = dataDirectory;
+			}
+		}
+
+		/// <summary>
+		/// Gets the data directory.
+		/// </summary>
+		/// <param name="host">The host object.</param>
+		/// <returns>The data directory.</returns>
+		protected string GetDataDirectory(IHostV30 host) {
+			lock(_syncLock) {
+				_dataDirectoryAlreadyRead = true;
+				if(string.IsNullOrEmpty(_dataDirectory)) return host.GetSettingValue(SettingName.PublicDirectory);
+				else return _dataDirectory;
+			}
+		}
+
+	}
+
+}